4x4 and AT problems HELP!

I just bought a 96 ranger xlt super cab. 59,000 on it and the 4X4 wont engauge or disengauge properly. i cant get it to engauge at all it just makes a grinding noise up front (sounds like its comin from the hubs). when it does go in (rare occasion) it will pop in and out while im driving. As for the tranny problem its the 4.oL automatic tranny and it slips goin into 4th i think and it when it goes in its hard. any suggestions as to what these things could be a huge help or how i could fix any of them. I just bought it 2 weeks ago and it seems like its fallin apart

I had the same problem with my 96 ranger xlt about 80k on it i replaced the hubs to manual. and it fixed the problem. a conversion kit and hubs costed like $150 total. works like a champ